1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a bottom cover that is adaptive for accommodating a liquid crystal display panel regardless of the size of the liquid crystal display panel.
2. Description of the Related Art
A liquid crystal display (hereinafter, referred to as ‘LCD’) device is a flat panel display device which controls the light transmittance of a light beam in response to a video signal, thereby displaying a picture. Specifically, the LCD has been widely applied due to its superior characteristics such as lightness, thinness, low power consumption driving, etc. For example, the LCD has been applied as a display device of a notebook computer and an office automation device. Further, there is a strong demand for a large-size LCD to satisfy the consumers.
Referring to FIG. 1, a liquid crystal display device of the related art includes a liquid crystal display panel 2; a backlight unit for irradiating light to the liquid crystal display panel 2; a support main or support frame 4 for housing the liquid crystal display panel 2 and the backlight unit; a cover bottom or bottom cover 16 which is at the bottom side of the support frame 4 to fix the backlight unit and supports the support frame 4; and a case top or top cover 6 which encompasses an edge of the liquid crystal display panel 2 and a side wall of the support frame 4.
The liquid crystal display panel 2 has liquid crystal cells arranged as an active matrix between upper and lower substrates, and a thin film transistor installed at each of the liquid crystal cells for switching a video signal. The refractive index of each of the liquid crystal cells is changed in accordance with a video signal to display a picture corresponding to the video signal. A gate driver circuit board 3A and a data driver circuit board 3B for applying drive signals to the thin film transistor are mounted on a lower substrate of the liquid crystal display panel 2. Further, polarizing sheets are respectively installed in front and rear surfaces of the liquid crystal display panel 2.
The backlight unit includes a lamp assembly 36 for receiving power from an external power supply to irradiate light to the liquid crystal display panel 2; a light guide panel 12 which guides the light exiting from the lamp assembly 36 toward the liquid crystal display panel 2; a reflection sheet 14 arranged in a rear surface of the light guide panel 12; and a plurality of optical sheets 10 for improving the efficiency of the light exiting from the light guide panel 12 toward the liquid crystal display panel 2.
The lamp assembly 36 includes a lamp 33 and a lamp housing 35 for protecting the lamp 33, and acts as a light source which supplies the light to the liquid crystal display panel 2. Specifically, the lamp housing 35 increases the efficiency of the light irradiated from the lamp to prevent the loss of the light.
The light guide panel 12 guides the light incident from the lamp assembly 36 with a fixed tilt angle to the liquid crystal display panel 2. At this moment, the reflection sheet 14 guides the light generated from the lamp 33 toward the light guide panel 12 and prevents the loss of the light generated from the lamp 33.
The optical sheets 10 direct the light slantingly incident from the surface of the light guide panel 12 and the reflection sheet 14 to vertically proceed to the liquid crystal display panel 2. In other words, the optical sheets 10 act to erect the direction of the light from the surface of the optical sheets 10.
The top cover 6 is made in a square band shape to have a plane part and a side part which are bent at a right angle. The top cover 6 encompasses the edge of the liquid crystal display panel 2 and the side of the support frame 4.
The backlight unit and the liquid crystal display panel 2 are deposited on the support frame 4.
The bottom cover 16 is combined with the support frame 4 to protect the backlight unit and the liquid crystal display penal 2 and to support the support frame 4. Specifically, the bottom cover 16 is located at the lowest surface of the liquid crystal display device and made from a metal material to reinforce the strength of the support frame 4 formed from a plastic material.
On the other hand, as the size of the liquid crystal display panel 2 of the related art increases, the backlight unit, the bottom cover 16, etc. have to become larger accordingly to fit the size of the liquid crystal display panel 2. In other words, the bottom cover 16 need to be redesigned in accordance with the change of the size of the liquid crystal display panel 2. Therefore, the manufacturing cost of the liquid crystal display device is increased.